Process for printing upon fabric or the like with at least one printing stencil



Feb. 2, 1965 J. F. ELSASSER 3,168,036

PROCESS FOR PRINTING UPON FABRIC OR THE LIKE WITH AT LEAST ONE PRINTING STENCIL SW w Filed Dec. 20, 1961 W W W W mmnul Iuvuvtafi 33A F E/sassm B1 UM 'U-AfKTM-W United States Patent ()fifice 3,168,036 Patented Feb. 2, 1965 3,168,036 PROCESS FOR PRINTING UPON FABRIC OR THE LIKE WITH AT LEAST ONE PRINTING STENCIL Johann F. Elsasser, Kirchberg, Bern, Switzerland Filed Dec. 20, 1961, Ser. No. 160,729 Claims priority, application Switzerland, Dec. 21, 1960, 14,190/ 60 1 Claim. (Cl. 101-129) The present invention generally relates to the art of performing a desired printing operation upon a fabric, web or otherwise and, more particularly, to a new and improved process for applying a desired impression, such as a pattern, upon a fabric in a continuous manner without necessitating that movement of the fabric be interrupted for executing the printing operation.

The present invention provides a printing process which is more expedient in comparison with heretofore known modes of printing wherein acceleration of the large masses of the machine components and bringing such into their rest position intermittently relieve one another. A machine construction operating according to the so-called stop and go working procedure has been disclosed by John T. Montague in his United States Patent 2,309,914, issued February 2, 1943. In accordance with such type of known printing processes the Web or fabric and the transport mechanism therefor, after having been displaced a predetermined extent, are brought into a position of rest in order to carry out the printing operation for repetition of the design pattern. This type of apparatus must thereafter again be accelerated to the normal operating speed for each following working operation. While machines operating according to a stop and go work cycle have proven to be satisfactory up to a specific point, it has been found that such apparatus was not completely satisfactory when it was necessary to carry out large scale production and when the speed of movement of the transport device or conveyer belt and the fabric to be printed which is secured thereto was very large. In such a situation, the periodic acceleration and stopping of the fabric to be printed and the conveyer belt for such fabric requires very large forces which makes it necessary to provide for extremely complicated constructions.

Accordingly, it is an important object of the present invention to provide an improved process for printing on fabrics or otherwise which is readily adapted for large scale production.

A further important object of the present invention is to provide an improved method for applying one or more impressions upon a material in a relatively simplified, economical and expedient manner.

Still another important object of the present invention is to provide an improved method of performing one or more printing operations upon a web of material which permits for continuous movement of said web of material even when said printing operation is being carried out.

Another important object of the present invention is to provide an improved method of printing upon fabrics or the like which allows for eflicient and relatively simplified processing and handling of said fabrics.

Yet a further important object of the present invention is to provide an improved method of executing successive printing operations upon a web of material or fabric while ensuring for continuity in the pattern design, and without requiring a large expenditure of power.

In accordance with the process of the present invention the web of material or fabric has continuously imparted thereto a uniform movement while one or more printing stencils also continuously move back and forth in a predetermined path of travel. During the printing operation, the respective printing stencils travel with the material or fabric and during this time the movement of the applying means, such as a squeegee or other expedient, takes place in order to provide the fabric with suitable coloring matter for performing the desired printing operation. Upon completion of the printing operation, the printing stencil is withdrawn from the fabric, moved in a direction opposite to the movement of said fabric, and brought into its new desired location so that the work cycle can be repeated as often as desired. The printing operation is particularly noteworthy insofar as it is not necessary to interrupt the movement of the fabric so that movement thereof is continuous even during said printing operation.

In accordance with the present invention for providing an improved process for printing upon a fabric or other material, there is provided at least one printing stencil which cooperates, for example, with two adjacent and parallelly arranged endless guide rails, which are continuously moved in an opposite direction with respect to one another. One of the guide rails may be constructed as an endless conveyer and supports the fabric or web upon which a printing operation is to be carried out, whereas the other guide rail may be in the form of a cable and supports a printing stencil which is adjustably mounted or positionable in a stencil carriage in which the stencil is adapted to be moved back and forth. The speed of movement of the two guide rails are related to one another in such a manner that for the printing operation the stencil can be moved by means of the stencil carriage with the same speed as the fabric. Upon completion of the printing operation the stencil carriage is moved in an opposite direction and preferably with the same speed as the fabric so that the printing operation can begin again upon application of a squeegee or the like and coloring matter to the fabric to perform such printing operation. Thereafter, the printing stencil is withdrawn from the fabric and displaced rearwardly, the printing stencil may then again be applied to the fabric which is to be impressed with the pattern and the process can repeat as often as desired. The printing stencil when being displaced from one printing position to the next may move through an annular path of travel, such as an elliptical one for example, although the particular path of travel through which such printing stencil moves is not to be considered as limiting to the teachings of the invention.

Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating a preferred mode 'of carrying out the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.

In the drawings:

FIGURE 1 schematically illustrates the path of travel of a fabric or web upon which a printing operation is to be performed;

FIGURE 2 schematically illustrates the movement of an applicator such as a squeegee across the fabric;

FIGURE 3 schematically illustrates the position of the squeegee after having completed a printing operation upon a portion of the fabric;

FIGURE 4 schematically illustrates the new position of the stencil frame prior to beginning a new printing operation; and

FIGURE 5 schematically illustrates the position of the stencil and squeegee for carrying out a further printing operation.

In accordance with the process of the present invention the web or fabric, which may be in the form of a continuous sheet or band, is initially secured or otherwise suitably fastened to a backing cloth for example. The thus mounted fabric is then carried by a suitable transport device, such as an endless conveyer, in a predetermined direction and with a uniform speed of movement. Thereafter, one or more printing stencils supported in a stencil box carried by a stencil carriage, in a manner known to the art, are brought into an operative printing position with respect to the fabric and generally with surface contact between the printing stencil and fabric taking place. As will be self-evident, the printing stencil may be constructed to impart any desired pattern or design to the fabric undergoing treatment.

When the printing stencil has assumed its required printing position, coloring matter or the like is immediately applied through the stencil and onto the fabric in order to impress the latter with the stencil pattern. The applying means for the coloring matter may be of known construction such as a scraper, wiper blade, squeegee or other suitable expedient generally employed in the fabric printing art. Naturally, the applying means may make any desired number of passes in any desired direction across the fabric toproperly impregnate the same with said coloring matter. Of course, as a. practical matter, it is desirable to keep the number of passes to a suitable minimum so that the production time is correspondingly enhanced. I have found that one or two passes of the applying means across the fabric is gen erally sufiicient for most purposes. It is to be appreciated that during such time as the printing stencil has assumed its printing positiomthe fabric and printing stencil move in a common direction and with the same speed.

Thus, during this time the stencil will always maintain I the same relative position with respect to the fabric, with the result that the movement of the fabric need not be interrupted and the printing operation can be carried out in a truly continuous manner.

After the color applying means has executed the required number of passes across the fabric proper, to suitably imbue the same with the coloring matter and impress the desiredpattern thereon, the printing stencil is raised away from therfabric and displaced'in a direction opposite to the direction of travel of said fabric. The printing stencil is then repositioned at a new desired location on the fabric so that the printing operation previously described can be repeated as many times as is desired. Generally, it is desirable to rearwardly displace the printing stencil to such an extent that said printing stencil, upon being lowered into its new printing position, will accurately register with the trailing portion of the previously formed pattern such that undesirable overlapping or voids between successive patterns will not cur, and the desired continuity of the design sought is achieved. I have also found it desirable, for example,.to return the printing stencil into a new printing position with the same or approximately the same speed that the fabric is moving, although it will be evident that other magnitudes of speed could be employed. In such a case, and in view of the relative movement between the'fabric and the stencil, the latter can be rearwardly displaced approximately one-half the length of the previously applied pattern. It will be apparent that the speed and extent of rearward displacement of the printing stencil may be determined in accordance with the condition of operation for carrying out the printing work cycle. 7

In order toprovide for further clarity in the description and understanding of the present invention, there is schematically shown in FIGURES 1-5 the various possible positions of the printing stencil and fabric during 7 execution of a work cycle in accordance with the previously described process. Thus, in FIGURE 1 there is schematically illustrated the direction of travel of a fabric or web of material A upon which a printing operation is to be performed. The web of material A is secured for example to an endless conveyor band, and above such material there is arrangeda printing stencil S which is supported for vertical raising and lowering movement in a stencil frame or box S of known construction. Generally, and as is known to the art, it is desirable to allow for relative movement of the printing stencil ,S within the stencil box S so that proper alignment of said printing stencil on the material can be carried out. In order to apply coloring matter or otherwise to the web of material A, there is provided color applying means of known construction such as the squeegee or wiper unit R which is adapted to be moved across the stencil S and for example at right angles to the direction of movement of the material A. After impressing the desired pattern or design upon the material A the stencil S can be moved away from said material. v

In FIGURE 2 the squeegee R is shown in a position where it has traveled over approximately one-half of the width of the material and has printed two diamondshaped patterns M upon the material A. In FIGURE 3 the squeegee R is shown in its end position after ithas completed'for example one transverse movement across the width of the fabric A, and is'further shown displaced approximately one-half of its length in the direction of movement of the material. In FIGURE '4 it can be seen that the stencil S exhibits a length K and is rearwardly displaced approximately one-half of its length through suitable'coupling with an opposed or oppositely moving carrier member or guide device and to such an extent that the stencil pattern approaches andproperly registers with the terminal junction of the previously formed pattern. In FIGURE 5 there is shown the position of the stencil at the beginning of a new printing operation with the squeegee being in position to again move acrossthe width of the material A for applying coloring matter to the fabric. As is known to the art, the printing stencil S may be detachably held in the stencil box S so that it can, as desired, be exchanged for other stencil forms; Further, any desired number of stencils may be employed. in accordance with the'aforedescribed process and which may operate simultaneously resulting advantage of increased and continuous production, among'others, as

I claim: I A method of printing a continuous pattern -,upon a web of material by means of a printing stencil, said method comprising the steps of:

(a) providing a continuous planar web of material having an upper and a lower surface;

(b) disposing the lower surface of said web of material upon a transport device;

(c) operating said transport device to'move said web of material at a constant speed in a forward longitudinal direction;

(d) positioning a printing stencil having a pattern thereon over the upper surface of said web of material; g

(e) lowering said printing stencil downward into superposed engagement with the upper surface of said web of material; V

(1) moving said lowered printing stencil with said web of material at said constant speed and in a forward longitudinal direction for a distance approximately equal to one-half the distance of the pattern;

(g) applying coloring material through'said printing stencil to impress said pattern onto'the upper surface of said web of material only during said movement through said approximate one-half distance;

(h) raising said printing stencil upward torernove said pattern from engagement with said web of material;

(i) moving said raised printed stencilat said constant speed but in a reverse longitudinal direction for said 7 approximate one-half distance; and,

previously mentioned herein.

5 (j) sequentially repeating steps (a) through (i) inelusive.

References Cited by the Examiner UNITED STATES PATENTS 1,411,788 4/22 Kellogg 1012 50 X 1,468,384 9/23 Hahn 101123 2,002,335 5/35 Barnard 101124 5 Montague 101115 Thomas et a1. 101123 Wenger 101126 Sarka 8333 Kerstan 101126 EUGENE R. CAPOZIO, Primary Examiner.

ROBERT A. LEIGHEY, ROBERT E. PULFREY,

Examiners. 

